Found 95 talks archived in Telescopes and instrumentation

Abstract

The 2nd generation VLT instrument Multi Unit Spectroscopic Explorer(MUSE) is going to be an integral field spectrograph with wide field of view and high spatial sampling. It is currently being built by a European consortium to see first light end of 2012. I will describe instrumental properties, show some details of the optomechanical design, present the data processing, and give some examples for possible scientific use.

Abstract

At the end of 2008, on ideas of teams from the Observatoire de la Côte d’Azur (OCA) and IAC, the CoRoT satellite observed the star HD 46375, known to host a non-transiting Saturn-mass exoplanet with a 3.023 day period. HD 46375 is the brightest star with a known close-in planet in the CoRoT accessible field of view. As such, it was targeted by the CoRoT additional program and observed in a CCD normally dedicated to the asteroseismology program, to obtain an ultra-precise photometric lightcurve and detect or place upper limits on the brightness of the planet. In addition, a ground-based support was simultaneously performed with the high-resolution NARVAL spectro-polarimeter to constrain the stellar atmospheric and magnetic properties. In this seminar, I will present the main results, in particular the stellar constrain we obtained thanks to the detection of the oscillation mode signature and the plausible detection of the planetary signal, which, if confirmed with future observations, would be the first detection of phase changes in the visible for a non-transiting planet.

Abstract

ExPo is an imaging polarimeter that has been built in Utrecht University. ExPo works in the visible, and it combines the dual-beam technique, together with very short exposure times and a high polarization sensitivity. After four successful campaigns at the William Herschel Telescope, we have obtained polarization images of circumstellar environments around T Tau's and Herbig Ae's stars, evolved (post-AGB) stars and planets like Venus and Saturn. Our results prove the utility of imaging polarimetry to characterize faint structures around very different objects. In this talk I will go through the instrument details, and I will show some of our science results.

Abstract

VIMOS is visible multi-object spectrometer operating on the VLT. The high multiplex of the VLT visible imager and multi object/integral-field spectrometer, VIMOS, makes it a powerful instrument for large-scale spectroscopic surveys of faint sources. Following community input and recommendations by ESO's Science and Technology Committee, it was decided to upgrade the instrument in phases. The first phase of the upgrade is described and included changing the shutters, installing an active flexure compensation system, replacing the detectors with CCDs with a far better red sensitivity and less fringing, and improving the data reduction pipeline.

Abstract

In recent years, many countries throughout the Middle East - in particular the more prosperous states - have made great progress in education, higher education, and scientific research. However, this has not often been matched by equivalent progress in astronomy and its related fields, despite the fact that many nations in the region consider astronomy a fundamental part of their cultural and scientific heritage. The current status of astronomy in the individual countries of the Middle East will be reviewed. The positive decision of the International Astronomical Union (IAU) (Commission 46) to take a proactive role through visits and consultancy in the region will also be discussed, including the founding of MEARIM - the Middle East and Africa Regional IAU Meeting (first meeting held in Cairo 2008). The challenges and proposals to move forward teaching and research in astronomy in the Middle East will be considered, with comments relating North African countries and new trends, including space research along with astronomical activities.

Abstract

3C 279, the first quasar discovered to emit VHE gamma-rays by the MAGIC telescope in 2006, was re-observed by MAGIC in January 2007 during a major optical flare and from December 2008 to April 2009 following an alert from the Fermi space telescope on an exceptionally high gamma -ray state. The January 2007 observations resulted in a detection on January 16 with significance 5.2 sigma, corresponding to a F(> 150 GeV)(3.8±0.8) 10^-11 ph cm-2 s-1 while the overall data sample does not show significant signal. The December 2008 - April 2009 observations did not detect the source. We study the multi-wavelength behaviour of the source at the epochs of MAGIC observations, collecting quasi-simultaneous data at optical and X-ray frequencies and for 2009 also gamma-ray data from Fermi. We study the light curves and spectral energy distribution of the source. The spectral energy distributions of three observing epochs (including the February 2006, which has been previously published in Albert et al. 2008a) are modelled with one-zone inverse Compton models and the emission on January 16, 2007 also with two zone model and with a lepto-hadronic model. We find that the VHE gamma-ray emission detected in 2006 and 2007 challenges standard one-zone model, based on relativistic electrons in a jet scattering broad line region photons, while the other studied models fit the observed spectral energy distribution more satisfactorily.

Abstract

CANARY is a technical demonstrator for the proposed EAGLE instrument for European ELT. EAGLE will have twenty Integral Field Units patrolling a 5 arcminute field and requires a new form of adaptive optics to provide the required image quality for its 0.0375 arcsec image sampling: Laser Guide Star Multi-Object AO. This entails several significant technical innovations: open-loop control, atmospheric tomography, and new calibration methods. The CANARY demonstrator is currently in its first, natural guide star, phase, and the first results have been obtained on sky. CANARY Phase A is described and the first results are presented. The next, laser guide star, phase is then outlined.

Abstract

A new method of imaging in the visible has given the highest resolution images ever taken anywhere. It needs a natural guide star of only 18.5 mag (I band). This talk will show how it can be done on the WHT, the VLT and even on the GTC.

Abstract

Developed since 2006 by the IAC and UPCT, FASTCAM is an optical camera which takes advantage of recently available low noise and fast read-out CCDs (with integration times ~30 ms) to perform speckle imaging of astrophysical sources. At high enough speed rate, the atmospheric turbulence - classically responsible for image degradation , i.e. seeing- can be frozen in the image, which permits us to implement "lucky imaging techniques". In this shared talk, we will review the principle and objectives of the instrument (mainly oriented so far towards the study of brown dwarfs), we will present the results obtained in different campaigns at the NOT and WHT telescopes stressing the effort towards high contrast and high resolution optical imaging potential which can be further enhanced with post-processing techniques. In this talk we will also discuss some ideas for future projects and scientific applications, possibly in conjunction with the GTC.

Abstract

I will present a short introduction to speckle imaging and the so-called speckle holography technique. Subsequently, I will present results of speckle observations with the VLT (NACO) and Keck (NIRC) telescopes. The experiments demonstrate that in the observed targets speckle imaging combined with holographic image reconstruction provides imaging quality that can compete with and even supersede current adaptive optics (AO) imaging systems. Speckle imaging is a way to achieve reliable, high-quality, diffraction limited imaging capacity at relatively low costs. I will discuss what would be the estimated performance of speckle cameras at the WHT and GTC and sketch possible concepts.